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New observations are presented which indicate that the large dispersion and scattering of the pulses from PSR1758-23 are caused by a dense screen of ionized material located along the line of sight. This reconciles the distances to the pulsar with that to SNR W28.
Following the passage of an interplanetary shock at approximately 0500 UT, a major geomagnetic storm developed on October 22-23, 1981. Numerous auroral substorms occurred during this storm leading to an AE index greater than 1000 nT. We have used the expanding/contracting polar cap (ECPC) model (Moses et al., 1989) and data from the Dynamics Explorer 2 spacecraft to study the ionospheric electric fields for 12 consecutive traversals of the polar regions. The ECPC model can determine the voltage drops across the dayside merging and nightside reconnection gaps. We determined the relationship of the AL index (i.e., the intensity of the westward electrojet) to the nightside reconnection potential drop. An excellent linear correlation was found between the nightside reconnection gap voltage drop and the AL index. These results show that the solar wind strongly drives the magnetosphere-ionosphere system throughout the geomagnetic storm. A substantial level of dayside merging seems to occur throughout the event. Nightside reconnection varies from satellite pass to satellite pass and within the substorm recovery phase. We find that tail reconnection is an important feature of the recovery phase of substorms.
Corrosion studies were carried out for wrought and cast NASA-23 alloy using electrochemical methods. The scanning reference electrode technique (SRET), the polarization resistance technique (PR), and the electrochemical impedance spectroscopy (EIS) were employed. These studies corroborate the findings of stress corrosion studies performed earlier, in that the material is highly resistant to corrosion.
This paper presents a final technical report and summary of research on Monitoring the Reprocessed Flux in MCG-5-23-16 with ASCA (Advanced Satellite for Cosmology and Astrophysics) and XTE (X Ray Timing Explorer).
The Boreal Ecosystem-Atmospheric Study (BOREAS) TE-23 (Terrestrial Ecology) team collected map plot data in support of its efforts to characterize and interpret information on canopy architecture and understory cover at the BOREAS tower flux sites and selected auxiliary sites from May to August 1994. Mapped plots (typical dimensions 50 m x 60 m) were set up and characterized at all BOREAS forested tower flux and selected auxiliary sites. Detailed measurement of the mapped plots included: (1) stand characteristics (location, density, basal area); (2) map locations diameter at breast height (DBH) of all trees; (3) detailed geometric measures of a subset of trees (height, crown dimensions); and (4) understory cover maps. The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).
Spin polarization of beta-emitting fragment Mg-23(I(sup pi) = 3/2(sup +), T(sub 1/2 = l1.3 s) produced through the projectile fragmentation process in Mg-24 + Au, Cu and Al collisions has been observed at 91 AMeV. General trend in the observed momentum dependence of polarization is reproduced well qualitatively by a simple fragmentation model based on the participant-spectator picture, for heavy and light targets. However the polarization behavior differs from this model in tern of zero crossing momentum, which become prominent in the case of Cu target, where the polarization is not monotone function of the fragment momentum.
In an investigation of the J-33-A-21 and the J-33-A-23 compressors with and without water injection, it was discovered that the compressors reacted differently to water injection although they were physically similar. An analysis of the effect of water injection on compressor performance and the consequent effect on matching of the compressor and turbine components in the turbojet engine was made. The analysis of component matching is based on a turbine flow function defined as the product of the equivalent weight flow and the reciprocal of the compressor pressure ratio.
The magnetic storm that commenced on June 22-23, 2015 was one of the largest storms in our current solar cycle, resulting from an active region on the Sun that produced numerous coronal mass ejections (CMEs) and associated interplanetary shock waves. On June 22 at 18:36 UT the magnetosphere was impacted by the shock wave on the magnetosphere. Observations from several spacecraft observed the dynamic response of the magnetosphere and ionosphere. MMS observatories in the near earth tail These low altitude measurements are correlated in the magnetosphere with particle flux dropouts measured by MMS We follow the timing of this storm in the ionosphere with the density depletions throughout the ISS orbits, DMSP drift velocities, and enhanced AMPERE Birkland currents. Together these observations and simulation results will be assembled to provide each region's context to the global dynamics and time evolution of the storm. The models during these event support and flesh out the puzzle of the global dynamics.
We report on the first observation of a radio-quiet Active Galactic Nucleus (AGN) inpolarized X-rays: the Seyfert 1.9 galaxy MCG-05-23-16. This source was pointed at with theImaging X-ray Polarimetry Explorer(IXPE) starting on May 14, 2022 for a net observing timeof 486 ks, simultaneously with XMM-Newton(58 ks) andNuSTAR(83 ks). A polarizationdegreeΠsmaller than 4.7% (at the 99% confidence level) is derived in the 2–8 keV energyrange, where emission is dominated by the primary component ascribed to the hot corona.The broad-band spectrum, inferred from a simultaneous fit to theIXPE,NuSTAR, and XMM-Newtondata, is well reproduced by a power law with photon indexΓ=1.85±0.01and ahigh-energy cutoffEC=120±15keV. A comparison with Monte Carlo simulations showsthat a lamp-post and a conical geometry of the corona are consistent with the observed upperlimit, a slab geometry is allowed only if the inclination angle of the system is less than 50◦
Explorer vii observations of solar cosmic rays
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Quasi-stellar objects with emission line red shifts having multiple absorption line red shifts
Performance tests on modified manual gas valve
Resistance weld monitoring of Centaur tanks
Resistance weld monitoring of Centaur tanks evaluated using ultrasonic and thermal expansion methods
Photo-optical instrumentation - Conference, Washington, D.C., August 1968, Volume 1
Nuclear and space radiation effects - NASA/IEEE Conference, University of California at San Diego, July 1970
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